Method for taking and transferring bacteria samples

ABSTRACT

A tape dispenser, having means for supporting a nondrying adhesive tape therein, includes a depending mandrel having a flat surface of predetermined area. Tape from the roll is unrolled and pulled over the mandrel with the sticky side out. The flat surface of mandrel covered with the tape is pressed on a surface to be tested for bacteria, and the contaminated tape, over the mandrel, is then pressed onto surface of a culture medium. By using gelatin-like culture medium, it may be held upside down for transfer of bacteria from the dispenser, to prevent extraneous contamination from airborne bacteria.

[451 May 9, 1972 [54] METHOD FOR TAKING AND TRANSFERRING BACTERIASAMPLES [72] Inventor: Rose J. Sterling, Denver, Colo.

Birko Chemical Corporation, Denver, Colo.

22 Filed: Jan.26, 1970 21 Appl. No.1 5,702

[73] Assignee:

Frobisher, Fundamentals of Microbiology" (1968) page 187. QR46 .F76

Primary ExaminerA. Louis Monacell Assistant Examiner.lames R. HoffmanAttorney-Richard D. Law

[57] ABSTRACT A tape dispenser, having means for supporting a nondryingadhesive tape therein, includes a depending mandrel having a flatsurface of predetermined area. Tape from the roll is unrolled and pulledover the mandrel with the sticky side out. The flat surface of mandrelcovered with the tape is pressed on a surface to be tested for bacteria,and the contaminated tape, over the mandrel, is then pressed ontosurface of a culture medium. By using gelatin-like culture medium, itmay be held upside down for transfer of bacteria from the dispenser, toprevent extraneous contamination from airborne bacteria.

4 Claims, 6 Drawing Figures PATENTEDMAY 9 I972 Z 3. 661 ,7 l 8 INVENTORJ. STERLING ROSE ATTORNEY METHOD FOR TAKING AND TRANSFERRING BACTERIASAMPLES The present invention relates to bacteria sampling, and moreparticularly to a novel method and improved apparatus for gatheringsamples of bacteria and transferring the bacteria samples to culturemedia.

I-Ieretofore, sterilized cotton swabs moistened with a sterilized liquidhave been employed for taking samples of bacteria from selectedsurfaces, such as equipment, walls and animal surface tissue, floors,etc. The samples once taken were transferred from the surface of themedia after which the samples were incubated. After predeterminedperiods of incubation, counts of the bacteria present in the cultureswere made. These bacteria counts which represent the bacteria present inthe bacteria samples were then compared to a predetermined standard, andthereby the degree of cleanliness of the selected surfaces from whichthe samples were taken was determined.

In using such bacteria sampling techniques wherein the bacteria countsof different samples are compared against a predetermined standardcount, or against each other, it is essential that the bacteria samplesbe taken uniformly in order to obtain meaningful results which are trulya measure of the relative cleanliness of the selected surfaces fromwhich the samples were taken. Consequently, with the use of cottonswabs, it has been found necessary to train technicians in the art ofgathering bacteria samples from selected surfaces and transferring thesesamples to cultures. In an attempt to obtain uniformity, one techniquetaught to technicians for gathering and transferring samples has been tolightly roll a swab across a selected surface, thereby to gather thebacteria sample, and thereafter to transfer the bacteria sample to theculture by lightly rolling the swab thereacross. A disadvantage inherentwith such a method of taking bacteria samples is that the uniformity ofthe samples taken primarily depends on the skill of the particularperson gathering the samples.

Accordingly, it is an object of the present invention to provide a novelmethod and improved apparatus for gathering and transferring bacteriasamples which obviates the disadvantages of the prior art.

It is further an object of the present invention to provide a novelmethod as set forth which is characterized by employing a non-dryingadhesive substance for gathering and transferring bacteria samples.

It is additionally an object of the present invention to provide animproved apparatus as set forth which employs a material having anadhesive surface for gathering and transferring bacteria samples in aconvenient, quick and uniform manner.

It is also an object of the present invention to provide a novelapparatus as set forth which is constructed in such a manner as toenable unskilled persons, as well as trained bacteriologists, to obtainuniform bacteria samples from selected surfaces.

In accomplishing these and other objects and advantages, there has beenprovided, in accordance with the present invention, a tape dispensingmeans including a roll of tape. The tape has a nondrying adhesivematerial on at least one side thereof and is dispensed so as to passacross a flat mandrel-like surface positioned on the tape dispensingmeans with the adhesive side out. Thereby, the tape may be positionedagainst the predetermined area, mandrel-like surface and bacteriasamples may be taken from a selected surface by employing the mandrel topress the adhesive side of the tape against the selected surface. Thebacteria sample is taken from a predetermined area of the selectedsurface and is transferred to a culture media such as an agar-agarculture medium by employing the mandrel to press the same adhesivesurface of the tape against the surface of the culture medium. The tapemay then be unrolled to position a fresh unused portion of the tape overthe mandrel, and another bacteria sample may be taken immediately. Meansare, also, provided on the tape dispensing means for severing portionsof the tape from the tape roll. Thus, there is provided an improvedapparatus for taking bacteria samples which enables unskilled personnelto take uniform bacteria samples by the novel method of using anondrying adhesive substance to gather bacteria samples from a selectedsurface and transfer the sample to a culture medium for incubation.

' A better understanding of the present invention may be had from thefollowing detailed description when read in conjunction with theaccompanying drawings, in which:

FIG. 1 is a pictorial representation of an apparatus for gatheringbacteria samples in accordance with the present invention;

FIG. 2 is a top view of the apparatus of FIG. 1 with a roll of adhesivetape positioned therein and being dispensed therefrom;

FIG. 3 is a sectional view taken along the line 33 of FIG. 2 showing thetape dispensed from the roll of adhesive tape and positioned for takingand transferring a bacteria sample;

FIG. 4 is a front elevational view of the apparatus of FIG. 1;

FIG. 5 is a pictorial view of the apparatus of FIG. 1 in position belowan upside down tray containing a gelled culture medium with-a cover forthe apparatus shown adjacent the apparatus; and

FIG. 6 is a side elevational view of a modified form of tape dispenser,according to the invention.

Referring to the FIGS. 1-4 in more detail, there is shown a tapedispensing means, indicated generally by the numeral 1, having a housing2. The housing 2 is formed by two interlocking sections 2a and 2b which,when joined, form a flat rectangular shaped box having a shaft 3centerally disposed therein and a slot-like opening 4 defined in oneside thereof. In one form, the rectangular shape of the box defined bythe housing 2 is generally square and the slot 4 is preferably locatedat approximately the center of one of the sides of the housing 2. Otherconfigurations of the dispenser may be utilized to meet therequirements. For example, an essentially round housing is satisfactoryfor many purposes.

The tape 5 is preferably loaded in the housing 2 under sterileconditions and housing seal for protection against contamination. Theroll of tape 5 is shown positioned in the dispensing means 1 in FIGS. 2and 3. In FIG. 2, the tape 5 is shown unrolled so as to extend throughthe slot 4 and over a depending mandrel 6.

The mandrel 6 is mounted on the side of the housing 1 adjacent the slot4. As shown in FIGS. 1 and 3, the mandrel 6 is mounted below the slot 3and is shaped to provide a flat surface 7 of predetermined areaextending away from the housing 2. Generally, the surface 7 issubstantially parallel with the side of the housing 2 upon which themandrel 6 is mounted. Where desired, the area may be rounded, ratherthan flat, to facilitate taking samples from various surfaces.

Mounted on the same side of the housing 2 as the mandrel 6 is a serratedcutting edge 8, near the upper end of the housing 2 above the slot 4.The cutting edge 8 is serrated to provide a simple and easy means forcutting used portions from the tape 5.

As shown in FIG. 2, the width of the tape 5 is slightly greater than thewidth of the mandrel 6. This is intentional so that the tape 5completely covers the mandrel 6, and when bacteria samples are takenwith the tape 5 the mandrel is not contaminated by the bacteria. Thisprevents accidental contamination of the tape from bacteria present onthe mandrel 6. Further, it is noted that the tape 5 preferably has anadhesive substance only on its inner surface 5a. The roll of tape 5,therefore, is positioned on the shaft 3 in the sense so that as the tape5 unwinds the outside surface 5b of the tape 5 passes over the surfaceof the mandrel 6. Thus, the adhesive surface 5a of the tape 5 facesoutward away from the dispensing means 1 when positioned across the flatsurface 7 of the mandrel 6. Since the surface 5a is the inner surface ofthe rolled tape, the adhesive surface 5a is in a sterile,non-contaminated condition as unwound from the tape roll 5.

Shown in FIG. 5 is one type of a cover 9 which may be placed over themandrel 6, if desired, whenever the dispensing means 1 is not in use,thereby, to prevent unnecessary contamination of the mandrel 6. Thedispensing means 1 is shown in FIG. positioned beneath a culture tray15. The tray 15 has a culture media 16 therein which may be, forexample, a nutrient broth, such as beef broth, containing a gelatinousor gum-like substance, such as agar-agar and gelled for use. The culturemedium tray 15 is divided into nine marked areas, each portion being forreceiving one bacteria sample. The tray 15 is shown turned upside downin FIG. 5 so that a bacteria sample gathered on tape 5 on the mandrel 6may be moved up into contact with the culture medium and transferred toit. The culture medium is normally clear and the tray is glass or clearplastic so the sample may be observed through the tray bottom.

In operation, a roll of adhesive tape 5 is positioned in the housing 2of the dispensing means 1 about the shaft 3. Tape 5 is then unwound fromthe tape roll and pulled over the mandrel 6 and its flat surface 7 asshown in FIG. 3. The tape 5 completely covers the surface 7 and theadhesive surface 5a of the tape 5 is positioned over the mandrel 6facing outward away from the housing 2. To take a bacteria sample from aselected surface, the dispensing means 1 and in particular, the flatsurface 7 of the mandrel 6, is used to press a predetermined area of theadhesive surface 5a of the tape 5 against the selected surface. Thisbacteria sample is then transferred to the culture 16in the tray 15 bypressing the tape over the mandrel end against the culture 16. Inpractice, the culture tray 15 is; turned upside down as shown in FIG. 5,and the bacteria sample is at that time transferred to one of thedivided sections of the culture 16.

After taking and transferring one bacteria sample, the tape 5 is furtheradvanced to a portion of unexposed tape pulled over flat surface 7 ofthe mandrel 6. Then a second bacteria sample may be taken andtransferred to a marked section of the culture 16. To take additionalbacteria samples, the tape procedure is merely repeated once a bacteriasample has been transferred to a marked section of the culture 16, theculture 15 is turned agar side up and placed in an incubation chamber.The bacteria samples are then incubated and observed after predeterminedperiods of time, such as 24 hours, 48 hours, etc. Bacteria counts aremade for each marked section of the culture 16, after the desiredinterval of incubation as is conventional. The bacteria counts may thenbe compared to predetermined standards to determine the relativecleanliness of the selected surfaces from which the bacteria sampleshave been taken.

The modification of FIG. 6 utilizes a generally round container 30having a tape roll supporting shaft 32 depending from one side of thecontainer. The container may for convenience be formed of two separablehalves. A depending mandrel 34, provided with a flat, predetermined areasurface 35, extends from the container, with one side of the mandrel ata tangent to periphery of the container. An elongated opening 38provides a slot through which the tape is dispensed. A depending bar 39extends across the top of the slot and from side to side thereof. Asecond depending bar 40 is spaced from the first bar and it extendsacross the container, both bars extending with their longitudinal axessubstantially parallel to the axis of the shaft. Adjacent to the secondbar, on the side opposite the first bar, is a serrated cutter 42. Tapeis mounted in the container so that as it is pulled out of the slot, theadhesive side is facing the bar 39.

In using the dispenser of FIG. 6, a length of tape is pulled from theroll, and wrapped around the mandrel 34 over the surface 35. A bacteriasample is taken, transferred to a culture medium, and the used portionpulled over the two depending bars 39 and 40 so that the bacterialsample section is beyond the bar 40. The adhesive sticks to the bars andthe used portion is readily cut off on the serrated cutter. The user maynow grasp the tape between two bars, elevated above the containersurface by two bars, and sufficient tape pulled out to wrap around themandrel for additional samples.

It IS noted that m a dispensing apparatus constructed in accordance withthe present invention, the flat surface on the mandrel 6 was dimensionedto have a size of approximately 52. inch X inch. A 36 inch tape has aslightly greater width than the anvil, and the exemplary dispensingapparatus constructed enabled one to conveniently take bacteria samplescovering an area of inch X 9%; inch (9/16 Sq. In.) from selectedsurfaces. Further, since to take and transfer a bacteria sample one isrequired to only press the flat surface 7 of the mandrel 6 against theselected surface to be sampled, it is apparent that no special skill isrequired to use the apparatus of the present invention. Additionally,numerous bacteria samples may be rapidly taken with the same roll oftape by merely advancing the tape sufficiently after each sampleto-position an unexposed and uncontaminated portion of the tape on themandrel surface. The exposed tape may be left intact with the tape rolluntil numerous bacteria tests have been taken. Thereafter, the exposedtape may be cut from the tape roll by means of the cutting edges andthen discarded. For storage, the mandrel, if desired, may be coveredwith a cover.

Thus, there has been provided an improved apparatus for taking bacteriasamples which enables even unskilled personnel to quickly andconveniently gather uniform bacteria samples. The bacteria samples aretaken by the novel method of using a predetermined size of surfacehaving an adhesive substance thereon to gather bacteria samples from aselected surface and to transfer the sample to a culture for incubation.The method is unique in sampling the same size of surface each time,which provides an accurate means of correlating bacteria counts ofvarious surfaces.

I claim:

1. The method of gathering a bacteria sample and transferring saidsample to a culture medium for incubation, comprising the steps of:

a. pressing a substantially nondrying adhesive surface against a surfacefrom which said sample is to be taken to gather said bacteria samplefrom said surface; and

b. pressing said adhesive surface against said culture medium totransfer said bacteria sample thereto.

2. The method recited in claim 1 including forming said adhesive surfaceof a predetermined area whereby uniform bacteria samples are taken.

3. The method recited in claim I including placing said adhesive surfaceon a mandrel of a predetermined size and shape with the adhesive sidedirected away from said mandrel.

4..The method recited in claim 1 including providing said adhesivesurface in tape form, unwinding said tape, and pulling said tape over amandrel prior to said pressing step.

UNITED STATES PATENT OFFICE- CERTIFICATE OF CORRECTION Patent No. 3 661718 Dated Mav .51 972 Inventor s J. Sterling ROSE It is certified thaterror appears in the above-identified patentv and that said LettersPatent are hereby corrected as shown below:

The name in the heading line directly under the words United StatesPatent is stated to be Sterling. The name should appear as Rose.

The name of the Inventor is stated to be Rose J. Sterling, and the nameshould appear as J. Sterling Rose.

Signed and sealed this 19th day of September 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Att esting Officer Commissionerof Patents FORM PO-105O (10459) USCOMM-DC 60376-P69 U.5. GOVERNMENTPRINTING OFFICE: I969 O356-334

2. The method recited in claim 1 including forming said adhesive surfaceof a predetermined area whereby uniform bacteria samples are taken. 3.The method recited in claiM 1 including placing said adhesive surface ona mandrel of a predetermined size and shape with the adhesive sidedirected away from said mandrel.
 4. The method recited in claim 1including providing said adhesive surface in tape form, unwinding saidtape, and pulling said tape over a mandrel prior to said pressing step.